VOLTCRAFT DSO1000E Series, DSO1000SE Series, DSO1000F Series User Manual

DSO1000E/SE/F Series

Digital Storage Oscilloscope

User Manual

（Version 1.4）

Copyright Decl aration

All rights reserved; no part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, without prior written permission from our company. Our company reserves all rights to modify this document without prior notice. Please contact our company for the latest version of this document before placing an order. Our company has made every effort to ensure the accuracy of this document but does not guarantee the absence of errors. Moreover, Our company assumes no responsibility in obtaining permission and authorization of any third party patent, copyright or product involved in relation to the use of this document.

Digital Storage Oscilloscope I

General Safety Summary

Read the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. To evade potential hazards, use this product only as specified.

Only qualified personnel should perform maintenance. Avoid fire or personal injury. Use suitable power cord. Use only the power cord specified for this product and

certified for the country of use. Connect and disconnect properly. Connect a probe with the oscillosc ope before it is connected to measured circuits; disconnect the probe from the oscilloscope after it is disconnected from measured circuits. Ground the product. This product is grounded through the grounding conductor of the power cord. To avoid electric shock, the grounding conductor must be connected to earth ground. Before making connections to the input or output terminals of the product, ensure that the product is properly grounded. Connect the probe in a r igh t way. The probe ground lead is at ground potential. Do not connect the ground lead to an elevated voltage. Check all terminal ratings. To avoid fire or shock hazard, check all ratings and markings on the product. Refer to the product manual for detailed information about ratings before making connections to the product. Do not operate without covers. Do not operate this product with covers or panels removed. Avoid exposed circuitry. Do not touch exposed connections and components when power is present. Do not operate with suspected failures. If you suspect there is damage to this product, have it inspected by qualified service personnel.

Assure good ventilation. Do not operate in wet/damp environments. Do not operate in an explosive atmosphere. Keep product surfaces clean and dry.

Digital Storage Oscilloscope II

Safety Terms and Symbols

Terms on the product. The following terms may appear on the product:

Danger It represents that harms may be caused to you at once if you perfor m the

operation.

Warning It represents that latent harms may be caused to you if you perform the

operation.

Notice It represents the damage possibly caused to the product or other

properties if you perform the operation.

Characters on the product. The following characters may appear on the product:

Notice

Please read

the manual

Protective

ground terminal

Measuring

ground terminal

Chassis

ground terminal

Product Scrapping

Device Recycling

We need extract and utilize natural resources to produce this device. If you do not reclaim the device in a proper way, some substances it contains may become harmful or poisonous to environments or human bodies. To avoid them being released outside and to minimize the waste of natural resources, we suggest you reasonably call back this device to ensure proper recovery and recycling of most materials within it.

Digital Storage Oscilloscope III

Brief Introduction to the Series of digital storage oscilloscope

DSO1000E/F Series osc illoscopes cover t he bandwidths from 80MHz t o 250MHz, and provide the real-time up to 1GSa/s. In addition, they have 7 inch color TFT LCD as well as WINDOWS-style interfaces and menus for easy operation. What’s more, the plenty menu information and the easy-to-operate buttons allow you to gain information as much as possible in measurement; the multifunctional knobs and the powerful shortcut keys help you save a lot of time in operation; the Auto Scale function lets you detect sine and square waves automatically; By using the three methods the oscilloscope provides (context-sensitive, hyperlinks, and an index), you may master all operations on the device in quite a short time so as to greatly improve your efficiency in production and development.

Model Channels Bandwidth Sample Rate AFG

DSO-1084E DSO-1104E DSO-1204E DSO-1254E DSO-1204E SE DSO-1084F DSO-1104F DSO-1204F DSO-1254F

4 80MHz 1GS/s 4 100MHz 1GS/s 4 200MHz 1GS/s 4 250MHz 1GS/s 4 200MHz 1GS/s 4 80MHz 1GS/s Yes 4 100MHz 1GS/s Yes 4 200MHz 1GS/s Yes 4 250MHz 1GS/s Yes

Digital Storage Oscilloscope IV

General Safety Summary ....................................................................................... II

Safety Terms and Symbols .................................................................................... III

Product Scrapping ................................................................................................. III

Brief Introduction to the Series of digital storage oscilloscope ............................... IV

Contents ................................................................................................................... V

Chapter 1 Introduction ........................................................................................ 1

1.1 General Inspection ................................................................................... 2

1.2 Prepare Instrument for Use ....................................................................... 3

1.3 Accidence of the user interface ................................................................. 4

1.4 Functional Check ...................................................................................... 5

1.4.1 Connect the oscilloscope ...................................................................... 5

1.4.2 Observe the waveform ......................................................................... 5

1.5 Probe Introduction .................................................................................... 6

1.5.1 Safety ................................................................................................... 6

1.5.2 Probe Check Wizard ............................................................................. 6

1.5.3 Manual Probe Compensation ............................................................... 6

1.5.4 Probe Attenuation Setting ..................................................................... 7

Chapter 2 Function Introduction ........................................................................ 9

2.1 Menu and Control Keys .......................................................................... 10

2.2 Connector ............................................................................................... 11

2.3 Universal Knobs and Softkeys ................................................................ 11

2.4 Oscilloscope Setup ................................................................................. 12

2.5 Horizontal Controls ................................................................................. 13

2.6 Vertical System ....................................................................................... 14

2.6.1 Vertical Controls ................................................................................. 14

Digital Storage Oscilloscope V

2.6.2 Math Operation ................................................................................... 16

2.7 Trigger System ....................................................................................... 20

2.7.1 Edge Trigger ....................................................................................... 22

2.7.2 Pulse Trigger ...................................................................................... 22

2.7.3 Video Trigger ...................................................................................... 24

2.7.4 Slope Trigger ...................................................................................... 25

2.7.5 Overtime Trigger ................................................................................. 26

2.7.6 Window Trigger .................................................................................. 27

2.7.7 Pattern Trigger .................................................................................... 28

2.7.8 Interval Trigger ................................................................................... 29

2.7.9 Under Amp Trigger ............................................................................. 30

2.7.10 UART Trigger ..................................................................................... 31

2.7.11 LIN Trigger ......................................................................................... 35

2.7.12 CAN Trigger ....................................................................................... 37

2.7.13 SPI Trigger ......................................................................................... 40

2.7.14 IIC Trigger .......................................................................................... 43

2.8 Save/Recall ............................................................................................ 47

2.8.1 Internal Save and Recall ..................................................................... 47

2.8.2 External save and recall ..................................................................... 48

2.9 Measure System ..................................................................................... 49

2.9.1 Scale measurement ............................................................................ 49

2.9.2 Cursor measurement .......................................................................... 50

2.9.3 Automatic Measurement ..................................................................... 51

2.10 Acquire ................................................................................................... 55

2.10.1 XY Mode ............................................................................................ 58

2.10.2 Roll Mode ........................................................................................... 58

2.11 Display ................................................................................................... 58

2.12 Utility System .......................................................................................... 59

2.12.1 Update Firmware ................................................................................ 60

2.12.2 Self Calibration ................................................................................... 60

2.12.3 Pass/Fail ............................................................................................ 61

2.13 Fast Action Buttons ................................................................................. 62

Digital Storage Oscilloscope VI

2.13.1 AUTO SCALE ..................................................................................... 62

2.13.2 Default Setup...................................................................................... 64

Chapter 3 Waveform Generator ........................................................................ 67

3.1 Set Wave Type and Parameters ............................................................. 68

3.2 Edit Arbitrary Waveform .......................................................................... 69

3.3 Output Arbitrary Waveform...................................................................... 71

Chapter 4 Troubleshooting ............................................................................... 72

4.1 Problem Settlement ................................................................................ 72

Chapter 5 General Care and Cleaning ............................................................. 74

5.1 General Care .......................................................................................... 74

5.2 Cleaning ................................................................................................. 74

Appendix A: Tec hnical Specifications ................................................................... 75

Appendix B: Accessories ....................................................................................... 82

Appendix C Harmful and Poisonous Substances or Elements ............................ 83

Appendix D To replace the fuse ............................................................................. 84

Appendix E Open Source Information ................................................................ 86

Digital Storage Oscilloscope VII

Chapter 1 Introduction

General Inspection



Prepare Instrument for Use



Accidence of the user interface



Functional Check



Probe Introduction

Digital Storage Oscilloscope 1

1.1 General Inspection

Please check the instrument as following steps after receiving an oscilloscope:

Check the shipping container for damage:

Keep the damaged shipping container or cushioning material until the contents of the shipment have been checked for completeness and the instrument has been checked mechanically and electrically.

Check the accessories:

Accessories supplied with the instrument are listed in "Accesso r i es " in t h is manual. If the contents are incomplete or damaged, please notify the franchiser.

Check the instrument:

In case there is any mechanical damage or defect, or the instrument does not operate properly or fails performance tests, please notify the franchiser.

Digital Storage Oscilloscope 2

1.2 Prepare Instrument for Use

Adjust the Supporting Legs

Adjust the supporting legs properly to use them as stands to tilt the oscilloscope upwards for stable placement of the oscilloscope as well as better operation and observation.

Connect the power cord as desired. Turn the instrument on by pressing the power switch in the lower left corner of front panel. If the instrument does not turn on, verify that the power cord is firmly connected (power-line voltage is automatically sensed at power-on). Also make sure that the instrument is connected to an energized power source. Power Switch:

To turn off the instrument, please press power switch.

Digital Storage Oscilloscope 3

1.3 Accidence of the user interface

This section will make you understand the front operation panel of this series of digital oscilloscope at first before use.

Figure 1-2 Interface display

1. Voltcraft logo

2. Trigger Status Auto: The oscill oscope works in auto mode and is acquiring waveforms in the

absence of triggers.

Ready: All pre-triggered data have been acquired and the oscilloscope is ready to

accept a trigger.

Roll: The oscilloscope is acquiring and displaying waveform data continuously in

roll mode.

Stop: The oscilloscope has stopped acquiring waveform data.

3. Readout shows main time base setting.

4. Sample rate.

5. Main Time Base Window

Digital Storage Oscilloscope 4

CH1: to connect with the probe

PROBE COMP

6. Tigger time

7. Trigger level, Readout tells trigger level.

8. Operating Menu shows different information for respective function keys.

9. If this icon lights up/active, it means the USB disk has been connected.

10. If this icon lights up/active, it means the wave generator works

11. The inf orm ation of coupling, B andwidth and volt/ di v of CH1~CH4.

12. Channel Marker

13. Window displays waveform.

1.4 Functional Check

Follow the steps below to perform a quick functional check to your oscilloscope.

1.4.1 Connect the oscilloscope

Set the switch on the probe to 10X and connect the probe to Channel 1 on the oscilloscope. First, align the slot in the probe connector with the protuberance on the CH1 BNC and push to c onnect; then, turn to right to lock the probe in place; aft er t hat, connect the probe tip and reference lead to the PROBE COMP connectors. The r e i s a mark on the panel: Probe COMP ~2V@1KHz.

1.4.2 Observe the waveform

Press the [Auto Scale] button and y ou should see within a few seconds a square wave of about 2V peak-to-peak at 1KHz in the display. Press the [CH1] MENU button twice to remove Channel 1. Push the [CH2] MENU button and repeat the st eps to observe CH2, CH3 and CH4.

Digital Storage Oscilloscope 5

1.5 Probe Introduction

1.5.1 Safety

When using the probe, keep your fingers behind the guard on the probe body to avoid electric shock. Do not touch metallic portions of the probe head while it is connect ed to a voltage source. Connect the probe to the oscilloscope and connect the ground terminal to ground before you start any measurements.

1.5.2 Probe Check Wizard

Every time you connect a probe to an input channel, you s hould use the probe check wizard to verify that this probe is operating correctly. Use the vertical menu (for example, push the [CH1] MENU button) to set the Probe attenuation factor.

1.5.3 Manual Probe Compensation

Upon the first connection of a probe and an input channel, you should manually perform this adjustment to match the probe to the input channel. Uncompensated or

Digital Storage Oscilloscope 6

Compensated correctly

Undercompensated

miscompensated probes may lead to errors or faults i n measurement. To adjust the probe compensation, follow the steps below.

1. Set the Probe option attenuation in the channel menu to 10X. Set the switch on the

probe to 10X and connect the probe to Channel 1 on the oscilloscope. If you use the probe hook-tip, ensure it is firmly inserted onto the probe. Attach the probe tip to the PROBE COMP ~2V@1KHz connector and the reference lead to the PROBE COM P Ground connector. Display the channel and then press the Auto Scale button.

2. Check the shape of the displayed waveform.

Overcompensated

3. If necessary, use a nonmetallic screwdriver to adjust the variable capacity of your

probe until the shape of the waveform turns to be t he same as the above figure. Repeat this step as necessary. See the figure below for the way of adjustment.

1.5.4 Probe Attenuati on Setting

Probes are of various attenuation factors which affect the vertical scale of the signal. The Probe Check function is used to verify if t he P robe attenuation option matches the attenuation of the probe. You can push a vertical menu button (such as the CH1 MENU button) and select the Probe option that matches the attenuation factor of your probe. Make sure that the Attenuation switch on the probe matches the Probe opti on in the oscilloscope. Switch settings are 1X and 10X. When the Attenuation switch is set to 1X, the probe limits the bandwidth of the oscilloscope to 6MHz. To use the full bandwidth of the oscilloscope, be sure to set the

Digital Storage Oscilloscope 7

switch to 10X.

Digital Storage Oscilloscope 8

Chapter 2 Function Introduction

This chapter provides some general information that you need to learn before using an oscilloscope. It contains:



Menu and Control Keys



Connector



Universal Knobs and Softkeys



Oscilloscope Setup



Horizontal Controls



Vertical System



Trigger System



Save/Recall



Measure System



Acquire



Display



Utility System



Fast Action Buttons

Digital Storage Oscilloscope 9

2.1 Menu and Control Keys

As shown in the figure below:

Figure 2-1 Control keys

All the keys are described as follows:

 [CH1], [CH2] , [CH3], [CH4]: display setup menus of channel 1 and channel 2.  [Math]: display “Arithmetical operation” waveform menu.  [Horizontal]: Set Horizontal system.  [Trig Menu]: display Trigger control menu.  [Force Trig]: It is used for finishing acquisition of the current waveform no matter

whether the oscilloscope detects trigger, and it is mainly applied to “Normal” and “Single” in the trigger mode.

 [Default]: recall the default factory setup.  [Help]: enter the on-line help system.  [Utility]: display “UTILITY FUNCTION” menu.  [Cursors]: display the “CURSOR” menu. The [V0] knob can be used for

regulating the position of the cursor when the “CURSOR” menu is displayed and the cursor is triggered.

 [Meas]: show the “Measure” menu.  [Wave Gen]: show the waveform generator menu.  [Save Recall]: show the “Save/Recall” menu of setups and waveform.  [Display]: show the “Display” menu.  [Auto Scale]: automatically set the control state of the oscilloscope so as to

display suitable waveform.

Digital Storage Oscilloscope 10

V0: menu options ( Press this knob to reset data (trigger holdoff, overtime of the overtime trigger and slope trigger), se

Press the waveform generator function.

 [Run/Stop]: continuously acquire waveform or stop acquisition  [Single]: Acquire a single trigger, finish acquisition and then stop.

2.2 Connector

Figure 2-2 Connector

 CH1, CH2, CH3, CH4: for an input connector of a measured signal.  EX T TRIG: be used as an input connector of an external trigger sourc e. Use

[Trig Menu] button to select “External” trigger source (only for Edge trigger), and the trigger signal source can be used for triggering in the third channel while acquiring data.

 Gen Out: Waveform signal output.  Probe compensation: T he probe compensation signal is output and grounded

so that the probe is matched with the channels of the oscilloscope.

2.3 Universal Knobs and Softkeys

Universal Knob. Under different menu options, it supports selecting

MEASURE), moving cursors and levels (Slope Trigger).

lect menu options and so on. Easy to operate.

Wave Gen button on the front panel to open the arbitrary

Digital Storage Oscilloscope 11

of the screen and give a full screen display of waveforms. Push it again to show the menu options.

functional. They are in charge of selecting corresponding menu options on the screen in different menu modes.

This functional softkey is mainly used to turn pages and confirm a

selection, such as

Hide/Show softkey. Push it to hide the menu options on the right side

-F5: These five softkeys are all multi-

‘next page’, ‘previous page’.

2.4 Oscilloscope Setup

While operating the oscilloscope, you may often use four features: Auto Scale, saving a setup, recalling a setup and default setup. Hereinafter they are introduced one by one. Auto Scale: This function can be used t o adjust the horizontal and vertical scales of the oscilloscope automatically and set the trigger coupling, type, positi on, slope, level and mode, etc., to acquire a stable waveform display. Saving a Setup: By default, the oscilloscope will save the setup each time before being closed, and automatic ally recall the setup once being turned on. (Note: If you modify the setup, please wait for more than 10 seconds before turning off the oscilloscope to ensure the proper s torage of new settings.) You can save 10 settings permanently in the oscilloscope and reset them as necessary. Recalli a Setup: The oscilloscope can recall any of your saved setups or the default factory setup. Default Setup: The oscilloscope is preset for normal operations when it is shipped from the factory. This is the default setup. You may recall this setup at any time for your requirements.

Digital Storage Oscilloscope 12

2.5 Horizontal Controls

Use the horizontal controls to change the horizontal scale and position of waveforms. The horizontal position readout shows the time represented by the center of the screen, using the trigger time as zero. When you change the horizontal scale, the waveform will expand or contract to the screen center. The readout near the upper right of the screen shows the current horizontal position in second. The oscill oscope also has an arrow icon at the top of the graticule to indicate the horizontal pos iti on.

1. Horizontal Position Knob: Used to control t he trigger position against the screen center. Push this button to reset the trigger point back to the screen center. AN: Used to set the horizontal position as zero.

Universal Knob

2.SEC/DIV Knob: Used to change the horizontal time scale so as to magnify or compress the waveform horizontally. If the waveform acquisition is stopped (by using the [Run/Stop] or [Single] butt on), the SEC/DIV control will expand or compress the waveform.

Note: Press SEC/DIV Knob to enter Dual-window Mode.

Digital Storage Oscilloscope 13

Location of expanded window data in memory

Minor Window

(Expanded Window)

Single-window Mode

Dual-window Mode (Full Screen)

Major Window

Press SEC/DIV Knob again to exit Dual-window Mode.

2.6 Vertical System

2.6.1 Vertical Controls

Vertical controls can be used to display and remove waveforms, adjust vertical scale and position, set input parameters and perform math calculations. Each channel has a separate vertical menu to set. See below for menu description.

Digital Storage Oscilloscope 14

resolution to small steps between the Coarse

Vertical Position

Volts/div

1. Vertical Position Knob: Move the channel waveform up and down on the screen. In dual-window mode, move the waveforms in both windows at the same time in a same direction. Push this knob to return waveforms to the vertical center position on the screen. Two channels correspond to two knobs. Also you can press this knob to switch between coarse and fine.

2. VOLTS/DIV Knob Control the oscilloscope to magnify or attenuate the source signal of the channel waveform. The vertical size of the display on the screen will change (increase or decrease) to the ground level.

3. Menu (CH1, CH2, CH3, CH4): Display vert ical menu options; turn on or off the display of channel waveforms.

Options Settings Comments

DC passes both DC and AC components of the input

Coupling

BW 20MHz

Div

DC AC GND

OFF ON

Coarse Fine

signal. AC blocks the DC component of the input signal and attenuates signals below 10Hz. Ground disconnects the input signal.

Limits the bandwidth to reduce display noise; filters the signal to eliminate noise and other unnecessary HF components.

Selects the resolution of the VOLTS/DIV knob. Coarse defines a 1-2-5 sequence. Fine changes the

settings.

Probe

10X 100X 1000X

Selects a value according to the probe attenuation factor so as to ensure correct vertical readouts. Reduce bandwidth to 6MHz when using a 1X probe.

Digital Storage Oscilloscope 15

The invert function turns the displayed waveform 180

trigger is also inverted.

Invert

Coupling

 If the channel adopts a DC coupling mode, you can quickly measure the DC

component of the signal by observing the difference between the waveform and the signal ground.

 If the channel adopts an AC coupling mode, the DC component in the signal is

filtered. By this mode, the AC component of the signal is displayed at a higher sensitivity.

 If the channel adopts a GND coupling mode, cut off the input signal. Inside the

channel, the channel input is connected with a zero volt reference electric level.

Fine Resolution

In the fine resolution setting, the vertical scale readout di splays the actual VOLTS/DIV setting. The vertical scale changes only after you adjust the VOLT S/DIV control and set to coarse.

Remove Waveform Display

To remove a waveform from the screen, first push the menu button to display the vertical menu, then push again to remove the waveform. A channel waveform which is unnecessary to be displayed can be used as a trigger source or for math operations.

OFF ON

degrees, with respect to the ground level. When the oscilloscope is triggered on the inverted signal, the

2.6.2 Math Operation

The series of scope supports many math operations between analog channels waveforms, including addition (+), subtraction (-), multiplication (*), division (/) and FFT. You can use cursors to measure it. The contents of this chapter:

• Units for Math Waveforms

• Math Operators

• To Adjust the Math Waveform Scale and Offset Note: If the analog channel or the math function display is truncated (waveforms do not display on the screen completely), the resulting math will also be truncated.

Digital Storage Oscilloscope 16

Operation Unit

Addition (+)or subtraction (-) V multiplication (*) division (/) None FFT dB, Vrms,

Addition or Subtraction

Math operators perform arithmetic operations - add or subtract operation - on any two analog input channels. When you select addition or subtraction, the Source A and Source B values are added or subtracted point by point, and the result is displayed.

1. Press the [Math] button on the front panel to enter the MATH function menu.

2. Press the Source 1 and Source 2 softkey respectively, and then turn the Universal Knob to select the source to do math operation. Analog channels (CH1~CH4) can be used as Source 1 or source 2.

3. Press the Operation softkey and then turn the universal to select + or -to make addition or subtraction operation. The resulting math waveform is displayed on the screen and labeled with “M”.

V∧2

Scale: Press the Scale s oftkey, and then turn the Universal Knob to select the vertical scale.

Digital Storage Oscilloscope 17

Multiplication and Division

Math operators perform arithmetic operations multiplication or divisi on operation on any two analog input channels. When you select multiplication or division, the Source 1 and Source 2 values are multiplied or divided point by point and the result is displayed.

1. Press the [Math] button on the front panel to enter the MATH function menu.

2. Press the Source 1and Source 2 softkey respectively, and then turn the Universal Knob to select the source to do math operation. Analog channels (CH1 ~CH4) can be used as Source 1 or source 2.

3. Press the Operation softkey and then turn the universal to select * or / to make multiplication or division operation. The resulting math waveform is displayed on the screen and labeled with “M”. Scale: Press the Scale s oftkey, and then turn the Universal Knob to select the vertical scale.

FFT Operation

FFT is used to compute the fast Fourier transform using analog input channels or reference waveforms. FFT takes the digitized time record of the specified source and transforms it to the frequency domain. When the FFT function is selected, the FFT spectrum is plotted on the oscilloscope display as magnitude in dBV versus frequency. The readout for the horizontal axis changes from time to frequency (Hertz) and the vertical readout changes from volts to dB. FFT operation can facilitate the following works:

 Measure harmonic components and distortion in the system  Measure the characteristics of the noise in DC power  Analyze vibration

To display a FFT waveform:

1. Press the [Math] butt on on the front panel to open the MATH function menu.

2. Press the Operation softkey and then turn the Universal Knob to select FFT. The resulting math waveform is displayed on the screen and labeled with “M”.

3. Press the Source soft k ey, and then turn the Universal Knob to select the source to do FFT operation. Analog channels (CH1~CH4) can be used as the source.

Digital Storage Oscilloscope 18

Window

Measurement

Characteristics

Waveform

same as no windows.

Waveform

Flattop

(Triangle)

stronger

Waveform

Better amplitude, poorer frequency accuracy than Hanning

4. Press Center softkey and then turn the Universal Knob to adjust the frequency of the frequency domain waveform corresponding to the horizontal center of the screen.

5. Press Span softkey and then turn the Universal Knob to adjust the the horizontal scale of the frequency domain waveform.

6. Pres s the Vertical Units softkey to select the unit of vertical axis. The units of the vertical axis can be dB or Vrms which use a logarithmic scale or a linear scale to display vertical amplitude respectively. If you need to display the FFT frequency spectrum in a relatively larger dynamic range, dBVrms is recommended.

7. Pres s the Scale softkey to select t he vert ical scal e.

8. Press the Window softkey, and then turn the Universal Knob to select an appropriate window. Spectral leakage can be considerably decreased when a window func tion is used. The series of scope provides six kinds of FFT window functions which have different characteristics and are applicable to measure different waveforms. You need to select the window function according to different waveforms and their characteristics. Please read the table below carefully to make an appropriate option according to the input signal.

Pulse or

Rectangular

Hanning

Hamming

Blackman

Bartlett

Flattop

Transient

Periodic

Transient or short pulse Single frequency signal, search for higher order harmonics. Narrow band

signal with

Periodic

Special-purpose window applicable to discontinuous waveforms. This is actually the

Better frequency, poorer a mplitude accuracy than

A litter bit better frequency resolution than Hanning.

The best amplitude resolution; the poorest frequency resolution

Better frequency resolution.

Digital Storage Oscilloscope 19

9. Pres s the Show-Only softkey to select to display FFT operation results only and not display the source channel.

Note:  Signals with DC components or deviation would cause an error or deviation of the FFT waveform components. To reduce the DC components, set the C hannel Coupling to AC.  To reduce the random noise and aliasing frequency components of repetitive or single pulse, set the Acquisition of the oscilloscope to Average.

Using Cursors to measure FFT waveform

To make cursor measurements, press the Cursors button to turn the cursors, and then press the Mode softkey to select Manual or Track, Use the AX and BX cursors to measure frequency values and the difference between two frequency values (BX-AX). Use the AY and BY cursors to measure amplitude in dB and difference in amplitude (BY-AY).

2.7 Trigger System

The trigger determines when the oscilloscope begins to acquire data and display a waveform. Once a trigger is properly set up, the oscilloscope can convert unstable displays or blank screens to meaningful waveforms. Here introduce some basic concepts about trigger. Trigger Source: The trigger can be generated with multiple sources. The most common one is the input channel (CH1~CH4). Whether the input signal is displ ayed or not, it can trigger normal operations. Also the trigger source can be any signal connected to an external trigger channel (only for Edge trigger). Trigger Mode: You can select the Auto or Normal mode to define how the oscilloscope acquires data when it does not detect a trigger condition. Auto Mode performs the acquisition freely in absence of valid trigger. It allows the generation of untriggered waveforms with the time base set to 100ms/div or slower. Normal Mode updates the displayed waveforms only when the oscilloscope detects a valid trigger condition.

Digital Storage Oscilloscope 20

Trigger Level

Indicates Trigger Points

Acquisition Interval

Acquisition

Before this update, the oscilloscope still displays the old waveforms. This mode shall be used when you want to only view the effectively triggered wveforms. In this mode, the oscilloscope displays waveforms only after the first trigger. To perform a single sequence acquisition, push the [Single] button. Trigger Position: The horizontal position control establishes the time between the trigger position and the screen center. Trigger Level: It sets the amplitude level the signal must cross to cause an acquisition when using the Edge or Pulse Width trigger. Force Trigger: Used to complete an acquisition regardless of an adequate trigger signal. This button becomes useless if the acquisition is already stopped.

Trigger Level

Holdoff: To use Trigger Holdoff, push the T rig Menu button and press Holdoff softkey. The Trigger Holdoff function can be used to generate a stable display of complex waveforms (such as pulse trains). Holdoff is the time between when the oscilloscope detects one trigger and when it is ready to detect another. During the holdoff time, the oscilloscope will not trigger. For a pulse train, the holdoff time can be adjusted to let the oscilloscope trigger only on the first pulse in the train.

Holdoff

Interval

Holdoff

Digital Storage Oscilloscope 21

2.7.1 Edge Trigger

Edge trigger distinguishes the trigger points by seeking the specified edge (rising, falling, rising & falling) and trigger level.

1. Press the [Trig Menu] button on the front panel to enter the Trigger system function menu.

2. Press the Type softkey, turn the Universal Knob to set select “Edge” and then push the knob to confirm.

3. Press the Source softkey, turn the Universal Knob to select CH1~CH4 or EXT as the trigger source.

4. Press the Slope softkey, turn the Universal Knob to select the desired trigger edge (rising, falling or rising & falling), and then press down the knob to confirm.

5. Turn the Trigger Level Knob to adjust the trigger level to obtain stable trigger.

6. Press o f 50% softkey to set the trigger level to the vertical midpoint bet ween the peaks of the trigger signal. The trigger level values are displayed at the upper right corner of the screen.

Note: Press the [Auto Scale] button will set the trigger type to Edge and slope to rising.

2.7.2 Pulse Trigger

Trigger on the positive or negative pulse with a specified width.

1. Press the [Trig Menu] button on the front panel to enter the TRIGGER function

Digital Storage Oscilloscope 22

+ 74 hidden pages